KR20160001260A - White organic light emitting display device - Google Patents

Abstract

A white organic light emitting display device according to an embodiment of the present invention includes an ambient light reflection blocking layer. The ambient light reflection blocking layer includes scattering particles or includes a microlens shape to block a phenomenon that ambient light incident to the white organic light emitting display device is reflected again and exits. The ambient light reflection blocking layer is positioned between an organic light emitting layer and an electrode layer having light transmittance so that the ambient light incident to the white organic light emitting display device reaches the ambient light reflection blocking layer before reaching an electrode layer having light reflectivity. The incident ambient light is scattered or is diffusion-reflected by the scattering particles of the ambient light reflection blocking layer, or a traveling direction is refracted in a close direction parallel to a plane of the white organic light emitting display device by the microlens of the ambient light reflection blocking layer. Accordingly, the incident ambient light is confined in any layer of the white organic light emitting display device or becomes extinct by destructive interference. Since the reflection of the incident ambient light is minimized, visibility of an image to be displayed by the white organic light emitting display device is further improved.

Description

WHITE ORGANIC LIGHT EMITTING DISPLAY DEVICE [0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a white organic light emitting diode (OLED) display, and more particularly, to a white organic light emitting diode (OLED) display capable of improving visible visibility by reducing external light reflection.

The organic light emitting display device is a self-emission type display device, unlike a liquid crystal display device, a separate light source is not required, and thus it can be manufactured in a light and thin shape. Further, the organic light emitting display device is not only advantageous from the viewpoint of power consumption by low voltage driving, but also excellent in color implementation, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next generation display.

On the other hand, in the case of an organic light emitting display device which realizes full-color light by the organic light emitting element, basically includes a red pixel, a green pixel and a blue pixel.

A method in which several organic light emitting layers are commonly laminated in all the pixels and light generated in each of several organic light emitting layers are combined to finally form white light by the organic light emitting element can be used. In this method, a color filter is required to realize color separately because the organic light emitting element forms white light. At this time, red light, green light and blue light are realized while the white light passes through the red color filter, the green color filter and the blue color filter corresponding to the respective red pixels, green pixels and blue pixels. Such an organic light emitting display device is referred to as a white organic light emitting display device. At this time, the white organic light emitting display device may further include a white pixel in addition to the red pixel, the green pixel, and the blue pixel. In a white pixel, white light formed in the organic light emitting element can be emitted as it is. Therefore, it is not necessary to provide a color filter in a white pixel.

However, in the past, the display device was mainly installed and fixed in a certain place in the room. However, in recent years, the use environment of the display device has been expanded in various ways in response to the various demands of users for the use of the display device. Accordingly, there are more and more factors to be considered in manufacturing the display device. For example, there is a portable display device such as a smart phone, a tablet PC and the like which can be used anytime and anywhere, a display device used for transportation such as a car or an airplane, In the case of a display device mainly used outdoors such as a commercial display device, a user uses the display device in a state in which the display device is exposed to external light such as sunlight. When the external light is incident on the display device, the metal wiring disposed in the driving element including the driving and switching thin film transistors, or the reflective electrode included in the organic light emitting element, or the layer of several layers constituting the display device The reflection of external light occurs due to the existence of the difference in refractive index. Such external light reflection is reflected from the display device together with the image that the display device ultimately provides to the user and is recognized by the user. As a result, the visibility of the display device is deteriorated. This is a problem that occurs without exception even when the organic light emitting display device is used.

In order to solve the problem of visibility due to external light reflection, conventionally, a method of providing a polarizing plate on the outside of the substrate in the direction of light emission has been proposed in the organic light emitting display device. At this time, the polarizing plate is composed of a combination of a linear polarizer which linearly polarizes the incident external light and a phase delay plate which delays the phase by? / 4. The principle of reducing the external light reflection by the polarizing plate is as follows. For example, when external light passes through the horizontal line polarizer while being incident, the incident external light is horizontally linearly polarized. Next, when the horizontal linearly polarized external light passes through the lambda / 4 phase delay plate, the incident external light is circularly polarized, for example, can be circularly polarized. Then, the left circularly polarized external light is reflected by the reflection electrode of the organic light emitting element and passes through the? / 4 phase delay plate again. At this time, the direction of the left circularly polarized light is changed to be right circularly polarized. Next, the right-handed polarized external light meets the horizontal line polarizer. Since the right-handed polarized external light can not pass through the horizontal line polarizer, external light can not escape from the organic light-emitting display and is confined, thereby reducing reflection of external light.

However, when the polarizing plate is used to minimize external light reflection in the organic light emitting display device, the light generated in the organic light emitting device also meets the polarizing plate in the emission direction. Therefore, more than 50% of the light generated in the organic light emitting device can not be escaped from the organic light emitting diode display by the polarizing plate and is confined, thereby reducing the luminance by more than half. Accordingly, if the driving current or the driving voltage is used as the high output to compensate for the reduced luminance, the deterioration of the organic light emitting layer progresses rapidly, thereby reducing the lifetime of the organic light emitting element.

Therefore, it is necessary to solve the problem of visibility due to reflection of external light, without providing a polarizing plate. Particularly, in the case of a white organic light emitting display device having a red pixel, a green pixel, a blue pixel and a white pixel, each of the green color filter, the green color filter and the blue color filter converts the external light, Absorbed. However, since the white pixel region without the color filter is in a state in which the external light is reflected and emitted as it is, the improvement of the visibility of the white pixel region is a problem to be solved more urgently.

The inventors of the present invention have found that the use of the polarizing plate of the present invention is advantageous in solving the problem of brightness reduction due to reduction in light extraction efficiency caused by use of the conventional polarizing plate as described above, A white organic light emitting display having a novel structure.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a white organic light emitting display capable of minimizing reflection of external light without a separate polarizing plate for minimizing external light reflection.

Another object of the present invention is to provide a white organic light emitting display capable of increasing light extraction efficiency and achieving higher luminance.

Another object of the present invention is to provide a white organic light emitting display having a thinner thickness.

The problems of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

There is provided a white organic light emitting display according to an embodiment of the present invention.

A white organic light emitting display device that does not include a polarizing plate includes a first substrate on which a red pixel region, a green pixel region, a blue pixel region, and a white pixel region are defined and includes a color forming layer located on a first substrate, A second electrode layer, and an encapsulating layer, wherein the color-forming layer includes an external light reflection-blocking layer and a color filter layer, and the color filter layer is formed so as to correspond to a red pixel region, a green pixel region, and a blue pixel region, respectively A first color filter, a second color filter and a third color filter which are separated from each other and located on the same plane, and the external light reflection prevention layer is located in the white pixel region.

According to still another aspect of the present invention, a color forming layer includes a first overcoat layer positioned between an external light reflection preventing layer and a color filter layer and alleviating or eliminating a step of a color filter layer, and a second overcoat layer positioned immediately adjacent to the external light reflection preventing layer, And a second overcoat layer for alleviating or eliminating the step difference.

According to still another aspect of the present invention, the external light reflection preventing layer is also located in the red pixel region, the green pixel region, and the blue pixel region.

According to still another aspect of the present invention, the external light reflection preventing layer overlaps the entire area of the color filter layer and is a single continuous layer in the red pixel region, the green pixel region, the blue pixel region, and the white pixel region.

According to another aspect of the present invention, the external light reflection preventing layer includes a first external light reflection blocking layer, a second external light reflecting blocking layer, and a second external light blocking layer separated to correspond to the red pixel region, the green pixel region, the blue pixel region, A third external light reflection preventing layer overlaps with the first color filter, a second external light reflection preventing layer overlaps with the second color filter, and a third external light reflecting layer, The blocking layer overlaps with the third color filter, and the fourth external light reflection blocking layer is located in the white pixel region.

According to still another aspect of the present invention, the fourth external light reflection blocking layer is located on the same plane as the color filter layer.

According to another aspect of the present invention, a second overcoat layer is disposed on the fourth external light reflection blocking layer and the color filter layer.

According to another aspect of the present invention, the first external light reflection blocking layer is in direct contact with the first color filter, the second external light reflection blocking layer is in direct contact with the second color filter, and the third external light reflection blocking layer is in contact with the third color filter As shown in FIG.

According to another aspect of the present invention, the area of the first external light reflection prevention layer is smaller than the area of the first color filter, the area of the second external light reflection prevention layer is smaller than the area of the second color filter, And the area of the reflection blocking layer is smaller than the area of the third color filter.

According to another aspect of the present invention, only a part of one surface of the first external light reflection blocking layer overlaps with one surface of the first color filter, or only a part of one surface of the second external light reflection blocking layer overlaps the surface of the second color filter Or only a part of one surface of the third external light reflection blocking layer overlaps one surface of the third color filter.

According to another aspect of the present invention, the external light reflection preventing layer includes scattering particles containing at least one selected from the group consisting of titanium oxide (TiO ₂ ), zirconium oxide (ZrO ₂ ), and barium titanate (BaTiO ₃ ) do.

According to another aspect of the present invention, the second overcoat layer is disposed in direct contact with the external light reflection preventing layer, and the second overcoat layer mitigates or removes a step of the external light reflecting and blocking layer. The refractive index of the external light reflecting / And has a refractive index value between refractive indexes.

According to another aspect of the present invention, the external light reflection preventing layer is formed in a microlens shape, and the microlens shape is concave or convex.

According to still another aspect of the present invention, the external light reflection preventing layer overlaps the entire area of the color filter layer and is a single continuous layer in the red pixel region, the green pixel region, the blue pixel region, and the white pixel region.

According to another aspect of the present invention, the microlens shape is located only in a region corresponding to the white pixel region.

According to another aspect of the present invention, in the color-forming layer, the external light reflection-blocking layer is located in the same plane as the color filter layer or under the color filter layer, the first electrode layer is located on the color- The first electrode layer is located on the first electrode layer, the second electrode layer is located on the organic light-emitting layer, is light-reflective, and the sealing layer is located on the second electrode layer.

According to another feature of the present invention, the first electrode layer is light-reflective, the organic luminescent layer is disposed on the first electrode layer, the second electrode layer is disposed on the organic luminescent layer and is light transmissive, In the color formation layer, the external light reflection prevention layer is positioned in the same plane as the color filter layer or on the color filter layer, and the encapsulation layer is located on the color formation layer.

The details of other embodiments are included in the detailed description and drawings.

The present invention can minimize external light reflection without having a polarizing plate for minimizing external light reflection.

In addition, the present invention can provide a white organic light emitting display with higher brightness by increasing the light extraction efficiency of a white organic light emitting display.

Further, the present invention can provide a white OLED display device having a thinner thickness.

In addition, the present invention can provide a white organic light emitting display in which the reflectance of external light is not rapidly changed according to the viewing angle and is stabilized.

The effects according to the present invention are not limited by the contents exemplified above, and more various effects are included in the specification.

1 is a cross-sectional view illustrating a white organic light emitting display according to an exemplary embodiment of the present invention.
2 to 7 are sectional views of a color forming layer for explaining a color forming layer of a white organic light emitting display according to an embodiment of the present invention.
8 is a cross-sectional view illustrating a white organic light emitting display according to another embodiment of the present invention.
9A and 10A are graphs showing the external light reflectance of the white organic light emitting diode display and the comparative example according to an embodiment of the present invention in the full wavelength range region.
FIGS. 9B and 10B are graphs showing the average external light reflectance obtained by averaging the external light reflectance of the entire wavelength range region of the white organic light emitting diode display and the comparative example according to another embodiment of the present invention, in the full-angle view region.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention, and the manner of achieving them, will be apparent from and elucidated with reference to the embodiments described hereinafter in conjunction with the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto.

Like reference numerals refer to like elements throughout.

In the following description of the present invention, detailed description of known related arts will be omitted when it is determined that the gist of the present invention may be unnecessarily obscured by the present invention.

Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used.

Includes plural instances unless the context clearly dictates otherwise. ≪ RTI ID = 0.0 > [0031] < / RTI >

In interpreting the constituent elements in this specification, even if there is no separate description, it is interpreted as including an error range.

In the case of the description of the positional relationship in the present specification, for example, when the positional relationship between two parts is described as 'on', 'on top', 'under', or 'next to' There may be more than one other part between the two parts, unless the 'right' or 'direct' or 'tangent' is used together.

In this specification, an element or layer is referred to as another element or layer "on ", including both intervening layers or other elements directly on or in between.

In the present specification, the refractive index means a refractive index at a wavelength of 550 nm unless otherwise stated.

Although the first, second, etc. are used in this specification to describe various components, these components are not limited by these terms. These terms are used only to distinguish one component from another. Therefore, the first component mentioned below may be the second component within the technical spirit of the present invention.

In describing the elements of the present invention in this specification, terms such as first, second, A, B, (a), (b) and the like can be used. These terms are intended to distinguish the components from other components, and the terms do not limit the nature, order, order, or number of the components. When a component is described as being "connected", "coupled", or "connected" to another component, the component may be directly connected or connected to the other component, Quot; intervening "or that each component may be" connected, "" coupled, "or " connected" through other components.

Like reference numerals refer to like elements throughout.

Herein, the area of any layer means the area of a large surface in the upper surface or the lower surface of any layer.

The sizes and thicknesses of the respective components shown in the drawings are shown for convenience of explanation, and the present invention is not necessarily limited to the sizes and thicknesses of the components shown in the drawings.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other partially or entirely and technically various interlocking and driving is possible as will be appreciated by those skilled in the art, It may be possible to cooperate with each other in association.

Hereinafter, a white OLED display according to various embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In the drawings, various layers that are components of a white organic light emitting diode display according to the present invention are represented by rectangles for the sake of convenience. Accordingly, the various layers may be in the form of a gentle curve, which appears to clearly distinguish between the front side and the side (side), but in fact the front and side are not clearly distinguished.

FIG. 1 is a schematic cross-sectional view of a bottom emission organic light emitting display according to an exemplary embodiment of the present invention. Referring to FIG.

In the organic light emitting diode display, the bottom emission scheme refers to a scheme in which light emitted from an organic light emitting diode is emitted toward a substrate on which a driving element including a thin film transistor for driving an organic light emitting display is located .

Referring to FIG. 1, a white organic light emitting display 100 including no polarizer according to an exemplary embodiment of the present invention includes a first substrate 110, a color forming layer 120, An electrode layer 131, an organic light emitting layer 132, a second electrode layer 133, and an encapsulation layer 140. 1, all the following drawings refer to red pixel region R, green pixel region G, blue pixel region B, and blue pixel region B, which are the minimum unit pixel bundles of white organic light emitting display 100, Only the sectional views of the four pixel regions in the white pixel region W are shown. In this case, for convenience of description, the respective pixels are shown as being arranged in the same width, but the structures of the pixels viewed from the plane other than the actual cross-section are not arranged in the same width, and may have various structures.

The first substrate 110 is formed of a transparent insulating material. For example, the first substrate 110 may be a glass substrate or a plastic substrate such as a polyimide having flexibility. A driving and switching thin film transistor including a gate electrode, an active layer, a source electrode and a drain electrode on the first substrate 110 and a metal wiring including a compensation circuit, a gate line, a data line, A driving element is formed. The organic light emitting element is driven by the driving element located on the first substrate 110. [ Respectively. The red pixel region R, the green pixel region G, the blue pixel region B, and the white pixel region (hereafter referred to as the first pixel region) W) can be defined.

The color forming layer 120 is formed in such a manner that the white light formed in the white organic light emitting diode display 100 emits red light, green light, and blue light in each of the red pixel region R, the green pixel region G, and the blue pixel region B, A color filter layer and an external light reflection preventing layer. The color forming layer 120 may have various structures as described below. The color filter layer is divided into a first color filter, a second color filter, and a third color filter, which are separated so as to correspond to each of the red pixel region R, the green pixel region G and the blue pixel region B, Filter. The first color filter is formed corresponding to the red pixel region R and can emit red light by absorbing light corresponding to a wavelength band other than the red wavelength in the white light generated in the organic light emitting layer 132. Alternatively, the energy of the white light generated in the organic light emitting layer 132 can be absorbed, and the red light can be generated and emitted directly by the energy. The second color filter is formed corresponding to the green pixel region G and can emit green light by absorbing light corresponding to a wavelength band other than the green wavelength in the white light generated in the organic light emitting layer 132. Alternatively, the energy of the white light generated in the organic light emitting layer 132 can be absorbed, and the green light can be directly generated and emitted by the energy. The third color filter is formed corresponding to the blue pixel region B and can emit blue light by absorbing the light corresponding to the wavelength band other than the blue wavelength in the white light generated in the organic light emitting layer 132. Alternatively, the energy of the white light generated in the organic light emitting layer 132 can be absorbed, and the blue light can be generated and emitted directly by the energy.

The organic light emitting device 130 includes a first electrode layer 131, an organic light emitting layer 132, and a second electrode layer 133.

The first electrode layer 131 is an electrode layer positioned in a direction in which light emitted from the organic light emitting layer 132 is emitted, and thus is light transmissive. In addition, since it has to function as an electrode, it has excellent electric conductivity. In addition, since the organic light emitting diode must be formed for every pixel region, the first electrode layer 131 connected to the driving thin film transistor is a pixel electrode separated for every pixel region. For example, the first electrode layer 131 may be connected to the source electrode or the drain electrode of the driving thin film transistor included in the driving device, and may include an anode. In this case, when the first electrode layer 131 is an anode, the work function of the first electrode layer 131 is high. That is, in the case of the bottom emission type, the first electrode layer 131 may include a material having conductivity and light transmittance and a high work function value and functioning as an anode, and may be separated to correspond to each pixel region. The first electrode layer 131 may be formed of a transparent conductive oxide (TCO) layer such as indium tin oxide (ITO), indium zinc oxide (IZO), or zinc oxide But are not limited to, materials.

The organic light emitting layer 132 forms white light. The organic light emitting layer 132 may include a plurality of light emitting portions (not shown) which are stacked with a charge generation layer (not shown) therebetween and which emit light of different colors. The color of the light emitted from the first light emitting portion (not shown) is complementary to the color of the light emitted from the second light emitting portion (not shown), and the light emitted from the first light emitting portion (not shown) (Not shown) are combined to finally form white light. For example, a charge generating layer (not shown) is disposed on a first light emitting portion (not shown) for generating yellow-green light and a second light emitting portion (not shown) for generating blue light on a charge generating layer ) Can be located.

The second electrode layer 133 is an electrode layer located on the opposite side of the direction in which light emitted from the organic light emitting layer 132 is emitted. Therefore, the second electrode layer 133 is light reflective. In addition, since it has to function as an electrode, it has excellent electric conductivity. For example, when the first electrode layer 131 includes an anode, the second electrode layer 133 may include a cathode. When the second electrode layer 133 is a cathode, the work function value of the second electrode layer 133 is lower than that of the first electrode layer 131. That is, in the case of the bottom emission type, the second electrode layer 133 includes a material having conductivity and light reflectivity and having a low work function value and functioning as a cathode. For example, the metal layer may include a single layer of a metal layer having a low work function value and excellent light reflectivity, or may include a metal layer having a low work function value and a metal layer having excellent light reflectivity, And may include an alloy of excellent metals or an alloy layer. The second electrode layer 133 may include, but is not limited to, an opaque conductive metal-based material such as aluminum (Al) or the like.

The sealing layer 140 functions to prevent the organic light emitting diode from being deteriorated as ultraviolet rays, oxygen, and moisture permeate into the white organic light emitting display device 100. The sealing layer 140 is formed by forming an ultraviolet curing sealant on the outermost side of the white organic light emitting diode display device 100 with the second electrode layer 133 formed thereon and locating a desiccant at the center, Method. Alternatively, the sealing layer 140 may be formed by forming a material containing an inorganic powder such as glass at the outermost edge of the white organic light emitting diode display device 100 in a state where the second electrode layer 133 is formed, Or by a flit sealing method. Alternatively, the sealing layer 140 may be formed by a face sealing method in which an ultraviolet ray or a thermosetting sealant is formed on the front surface of the white organic light emitting display device 100 with the second electrode layer 133 formed thereon . Alternatively, the sealing layer 140 may be formed by a thin film encapsulation (TFE) method including a protective layer containing an inorganic material and an organic insulating layer alternately laminated in sequence. At this time, the inorganic material includes at least one selected from aluminum oxide, zinc oxide, zirconium oxide, hafnium oxide, lanthanum oxide, titanium oxide, silicon nitride, and silicon oxide. At this time, the organic insulating layer functions to cover the foreign object and flatten the surface.

For a more detailed description of the color forming layer of the white OLED display 100 according to an embodiment of the present invention, reference will be made specifically to FIGS. 2 to 7.

2, the color forming layer 220 includes a color filter layer 250, a red pixel region R, a green pixel region R, a green pixel region R, a red pixel region R, and a green pixel region R, which are located only in the red pixel region R, the green pixel region G, The first overcoat layer 250 is located on the color filter layer 250 in the region G and the blue pixel region B and is not located in the white pixel region W, An external light reflection blocking layer 270 located on the first overcoat layer 261, and a second overcoat layer 262 located on the external light reflection blocking layer 270. [

At this time, the color filter layer 250 is divided into a first color filter 251, a second color filter 252, and a third color filter 253 which are separated to correspond to the red pixel region R, the green pixel region G, and the blue pixel region B, A second color filter 252 and a third color filter 253. The color filter layer 250 may comprise a material having a refractive index of about 1.5. The first overcoat layer 261 located on the color filter layer 250 alleviates or removes the step of the color filter layer 250. The first overcoat layer 261 may comprise a transparent insulating material having a refractive index of about 1.5. For example, it may be formed of one of acrylic resin, epoxy resin, phenol resin, polyimide resin, unsaturated polyester resin, polyphenylene resin, polyphenylene sulfide resin, benzocyclobutene and photoresist Any transparent insulating material having a refractive index of about 1.5 may be used without limitation.

Although the color filter layer 250 is not shown in the white pixel region W, the color filter layer 250 may be positioned in some cases. For example, a blue color filter that absorbs a part of the incident external light and compensates for the luminous efficiency of a blue pixel having a lower luminous efficiency than that of a relatively different pixel may be located in the white pixel region W. [ The external light reflection blocking layer 270 located on the first overcoat layer 261 overlaps the entire area of the color filter layer 250 and the red pixel region R, the green pixel region G, and the blue pixel region B ) And the white pixel region (W).

At this time, the external light reflection blocking layer 270 may be an external light reflection blocking layer 270 capable of photo-patterning including scattering particles, an alkali-soluble resin, and an unsaturated ethylenic monomer.

The scattering particles may be a metal oxide containing at least one selected from titanium oxide (TiO2), zirconium oxide (ZrO2), and barium titanate (BaTiO3), or the scattering particles may be hollow particles including a gas portion. When the difference between the refractive index of the scattering particles and the refractive index difference of the alkali-soluble resin is 0.2 or more, the external light incident on the white organic light emitting display device is reflected by the second electrode layer and may be extinguished when diffused again. The hollow particles may include a gas portion and a peripheral portion surrounding the gas portion, wherein the gas portion is composed of air, nitrogen, oxygen, etc., and the peripheral portion is a material having a refractive index of the alkali-soluble resin and the same refractive index as the refractive index of the unsaturated ethylenic monomer ≪ / RTI > In the present specification, the two values being the same mean both cases in which the two values are not identical but substantially the same. That is, when two values are equal, the two values are substantially the same in consideration of the error range, process variation in the manufacturing process, and the like. The diameter of the scattering particles is similar to or smaller than the wavelength of the incident external light. More specifically, the diameter of the scattering particles is 200 nm to 1 占 퐉. When the external light incident on the white organic light emitting display device meets scattering particles having a diameter that is similar to or smaller than the wavelength of the scattered particles, the scattered particles change into light having an electromagnetic wave component traveling in an irregular direction in all directions while causing strong scattering. The external light having such a characteristic can not reach the second electrode having the light reflectivity and is confined to any layer or is destroyed by extinction interference. When the diameter of the scattering particles is less than 200 nm, the scattering particles are not recognized due to the external light, irregular reflection does not occur. When the diameter of the scattering particles exceeds 1 탆, the material stability is poor, The characteristics of the device are deteriorated. Here, the diameter of the scattering particles means an average of the diameter of the scattering particles through particle size analysis.

The alkali-soluble resin may be a copolymer. For example, the alkali-soluble resin may contain one or more compounds selected from an unsaturated carboxylic acid and an unsaturated carboxylic acid anhydride, an epoxy group-containing unsaturated compound, an unsaturated carboxylic acid and an unsaturated carboxylic acid An unsaturated carboxylic acid anhydride and an olefinically unsaturated carboxylic acid ester compound other than an anhydride unsaturated carboxylic acid ester compound and an olefinically unsaturated compound other than an unsaturated carboxylic acid anhydride and an olefinically unsaturated carboxylic acid ester compound .

The unsaturated ethylenic monomer may be an acrylic monomer having two or more unsaturated ethylene bonds. Specifically, the unsaturated ethylenic monomer may be a polyfunctional acrylic monomer having two or more unsaturated ethylene bonds, and may be monofunctional, bifunctional or trifunctional or more in terms of good polymerizability, heat resistance and surface hardness of the resulting film. (Meth) acrylate may be used as an unsaturated ethylenic monomer.

The second overcoat layer 262 is located on the external light reflection blocking layer 270 to alleviate or remove the step of the external light reflection blocking layer 270. Thereby, the first electrode layer located on the second overcoat layer 262 can also be alleviated or flattened. That is, the second overcoat layer 262 has a portion where the top surface of the first electrode layer is sharp and the morphology changes abruptly due to the non-flattened top surface of the external light reflection blocking layer 270, so that the organic light- It is possible to prevent an unreformed region from being generated and to prevent the first electrode layer and the second electrode layer from being short-circuited.

The second overcoat layer 262 may have a refractive index close to the refractive index of the first electrode layer. More specifically, the second overcoat layer 262 may be a transparent insulating material having a refractive index between the refractive index of the external light reflection blocking layer 270 and the refractive index of the first electrode layer. For example, the second overcoat layer 262 may comprise a material having a refractive index of 1.65 or greater and having a transmittance of 80% or greater at a thickness of 1 [mu] m. For example, the high-refractive-index planarization film 270 may be formed of a polymer material including a metal oxide such as titanium oxide (TiO ₂ ) or zirconium oxide (ZrO ₂ ), a high refractive index material such as silicon nitride (SiNx) Materials and high refractive index polyimide. However, it is not limited thereto, and any transparent insulating material having a refractive index of about 1.65 or more may be used.

3, the first color filter 351 is located corresponding to the red pixel region R in the color forming layer 320, the second color filter 352 is located corresponding to the green pixel region G And the first color filter 351 and the first overcoat layer 372 correspond to the red pixel region R and the blue pixel region B and the first color filter 353 corresponds to the red pixel region R, The second external light reflection blocking layer 372 is located on the second color filter 352 and the first overcoat layer 361 corresponding to the green pixel region G and the third external light reflection layer 372 is located on the second color filter 352. [ The blocking layer 373 is positioned on the third color filter 353 and the first overcoat layer 361 in correspondence with the blue pixel region B and the second overcoat layer 362 is formed on the external light reflection- .

The color forming layer 320 of FIG. 3 is the same as the color forming layer 220 of FIG. 2 except for the form of the external light reflecting layer 370.

The external light reflection blocking layer 270 overlaps the entire area of the color filter layer 250 and is a single continuous layer in all the pixel areas. However, as shown in FIG. 3, May be patterned rather than a continuous single layer in all pixel regions. More specifically, in the case of the external light reflection preventing layer 370 including scattering particles, an alkali-soluble resin and an unsaturated ethylenic monomer, by photolithography patterning by a relatively simple process such as exposure and development, But may be patterned rather than a continuous single layer in all pixel regions. That is, the external light reflection blocking layer 370 is located on the entire area of the color filter layer 350 and the red pixel region R, the green pixel region G, the blue pixel region B and the white pixel region W A second external light reflection prevention layer 372, a third external light reflection prevention layer 373, and a fourth external light reflection prevention layer 374 that are separated to correspond to the first external light reflection prevention layer 371, the second external light reflection prevention layer 372, At this time, the first external light reflection blocking layer 371 is located on the first color filter 351, the second external light reflection blocking layer 372 is located on the second color filter 352, The layer 373 may be located on the third color filter 353 and the fourth external light reflection blocking layer 374 may be located on the white pixel region W. [

For example, only a part of the lower surface of the first external light reflection prevention layer 371 overlaps the upper surface of the first color filter 351, or only a part of the lower surface of the second external light reflection prevention layer 372 is the second color filter 352, or only a part of the lower surface of the third external light reflection preventing layer 373 may overlap with the upper surface of the third color filter 353.

Alternatively, if the area of the first external light reflection prevention layer 371 is smaller than the area of the first color filter 351 and the area of the second external light reflection prevention layer 372 is smaller than the area of the second color filter 352 Or the area of the third external light reflection blocking layer 373 may be smaller than the area of the third color filter 353. That is, the external light reflection blocking layer 370 is not located on the entire area of the first substrate, and all the regions of the external light reflection blocking layer 370 may be located only on the color filter layer 350. Therefore, the area of the external light reflection blocking layer 370 is equal to the area of the color filter layer 350 or smaller than the area of the color filter layer 350.

The area of the first external light reflection preventing layer 371 is smaller than the area of the first color filter 351 and only a part of the lower surface of the first external light reflecting and blocking layer 371 is located on the upper surface of the first color filter 351 Or the area of the second external light reflection preventing layer 372 is smaller than the area of the second color filter 352 and only a part of the lower surface of the second external light reflecting prevention layer 372 is overlapped with the second color filter 352 Or the area of the third external light reflection prevention layer 373 is smaller than the area of the third color filter 353 and only a part of the lower surface of the third external light reflection prevention layer 373 is overlapped with the third color And can overlap with a part of the upper surface of the filter 353.

4, the color forming layer 420 includes a first color filter 451 corresponding to the red pixel region R, a second color filter 452 corresponding to the green pixel region G, The third color filter 453 is positioned corresponding to the blue pixel region B and the first external light reflection blocking layer 471 is positioned directly adjacent to the first color filter 451 corresponding to the red pixel region R, The second external light reflection blocking layer 472 is located directly in contact with the second color filter 452 in correspondence with the green pixel region G and the third external light reflection blocking layer 473 is located in correspondence with the blue pixel region B The fourth external light reflection blocking layer 474 is located on the same plane as the color filter layer 450 corresponding to the white pixel region W and the second external light blocking layer 474 is located on the external light reflection blocking layer 470 The second overcoat layer 462 is located.

The color forming layer 320 of FIG. 3 is similar to the color forming layer 320 of FIG. 3 except that the color forming layer 420 of FIG. 4 does not include the first overcoat layer so that the color filter layer 450 and the external light reflection preventing layer 470 are directly adjacent to each other. .

5, the color forming layer 520 includes a color filter layer 550, a red pixel region R, and a green pixel region R, which are located only in the red pixel region R, the green pixel region G, and the blue pixel region B, Since the color filter layer 550 is located in the region G and the blue pixel region B and no separate color filter is disposed in the white pixel region W, A second overcoat layer 580, and a second overcoat layer 562 located on the external light reflection blocking layer 580. At this time, the external light reflection blocking layer 580 overlaps the entire area of the color filter layer 550, and is a single continuous layer in all the pixel areas, and the entire area of the external light reflection blocking layer 580 is a concave or convex microlens shape .

5 does not include the first overcoat layer so that the color filter layer 550 and the external light reflection prevention layer 580 are directly in contact with each other and the external light reflection prevention layer 580 is in a concave or convex micro lens shape The coloring layer 220 is the same as the coloring layer 220 of FIG. Hereinafter, the added or changed portions will be described.

The external light reflection blocking layer 580 may be formed in a concave or convex microlens shape. At this time, the external light reflection preventing layer 580 may include a plurality of concave or convex microlenses. At this time, the microlens shape may be a shape in which a plurality of concave or convex microlenses are randomly located, or may be an array shape. At this time, the microlens shape is hemispherical or semispherical. At this time, the microlens shape has an aspect ratio of 0.5 or more and 0.7 or less. At this time, the diameter of each of the microlens shapes is 1 占 퐉 or more and 8 占 퐉 or less, and the height is 1 占 퐉 or more and 4 占 퐉 or less. The external light incident on the white organic light emitting display device may be refracted so as to be substantially parallel to the surface of the white organic light emitting display device while meeting the microlens before reaching the second electrode layer having light transmittance. The incident external light is refracted by the microlens, and finally it is trapped in any layer in the white organic light emitting display without reaching the second electrode layer. That is, the white organic light emitting display device. The external light reflection blocking layer 580 may be formed using a light-transmitting photoresist material of a negative type or a positive type. However, it is not limited thereto, and any light-transmitting insulating material having a refractive index of about 1.5 is possible. When the photoresist material is spin-coated, it can be formed to a maximum thickness of 4 탆. In forming the microlens shape through the photolithography process, the diameter of the microlens shape can be formed to 8 탆, which is twice the thickness of the photoresist material.

Although the first overcoat layer is not shown on the color filter layer 550, the first overcoat layer may be located on the color filter layer 550 in some cases.

Although not shown in the figure, when the color filter layer 550 is not located in the white pixel region W, the microlens shape in the external light reflection preventing layer 580 is a shape corresponding to the white pixel region W in all the pixel regions Area. ≪ / RTI > That is, the microlens shape may be formed so as not to overlap with the color filter layer 550. Alternatively, when the color filter layer 550 is not located in the white pixel region W, the external light reflection blocking layer 580 may be located only in a region corresponding to the white pixel region W in all the pixel regions. That is, the external light reflection blocking layer 580 may be formed so as not to overlap with the color filter layer 550.

6, the color forming layer 620 includes a color filter layer 650, a red pixel region R, and a green pixel region R, which are located only in the red pixel region R, the green pixel region G, and the blue pixel region B, Since the color filter layer 650 is located in the region G and the blue pixel region B and no separate color filter is disposed in the white pixel region W, A second overcoat layer 662 positioned on the external light reflection blocking layer 680, and a second overcoat layer 662 located on the external light reflection blocking layer 680. That is, the external light reflection blocking layer 680 overlaps the entire area of the color filter layer 650 and is a continuous single layer in all the pixel areas, and the external light reflection blocking layer 680 may be formed in a concave or convex micro lens shape At this time, the microlens shape may be formed so as to correspond to all the pixel regions instead of the entire region of the external light reflection blocking layer 680. That is, in the external light reflection blocking layer 680, which is a continuous single layer in all the pixel regions, a portion corresponding to the gap between the first color filter 651, the second color filter 652 and the third color filter 653 The microlens shape may not be formed in the region.

The color-forming layer 620 of FIG. 6 is the same as the color-forming layer 620 of FIG. 6 except that the concave or convex microlens shapes included in the external light reflection blocking layer 580 are not continuous in all the pixel regions but are formed so as to correspond to all the individual pixel regions Is the same as the color-forming layer 520 in Fig.

7, the color forming layer 720 includes a first color filter 751 corresponding to the red pixel region R, a second color filter 751 corresponding to the green pixel region G, The third color filter 753 is located corresponding to the blue pixel region B and the first external light reflection blocking layer 781 is positioned directly adjacent to the first color filter 751 corresponding to the red pixel region R The second external light reflection blocking layer 782 corresponds to the green pixel region G and the third external light reflection blocking layer 783 corresponds to the blue pixel region B The second overcoat layer 762 is positioned on the external light reflection prevention layer 780 and the fourth external light reflection prevention layer 784 is positioned on the white color pixel area W And may be positioned in the same plane as the color filter layer 750.

The color-forming layer 720 of FIG. 7 is the same as the color-forming layer 420 of FIG. 4 except that the external light reflection blocking layer 780 is formed in a concave or convex microlens shape. At this time, the microlens shape included in the external light reflection blocking layer 780 and the external light reflection blocking layer 780 at this time is the micro-lens shape including the external light reflection blocking layer 580 and the external light reflection blocking layer 580 shown in FIG. It is the same as the lens shape.

As described above, the white OLED display according to an exemplary embodiment of the present invention includes an external light reflection prevention layer. The external light reflection blocking layer includes scattering particles or a microlens shape in order to prevent the external light incident on the white organic light emitting display device from being reflected and emitted again. The external light reflection blocking layer is positioned between the organic light emitting layer and the light transmissive electrode layer so that the external light incident on the white organic light emitting display device can meet the external light reflection blocking layer before reaching the light reflective electrode layer. The incident external light is scattered by the scattering particles of the external light reflection blocking layer or diffused irregularly in all directions or the traveling direction is refracted in the direction close to parallel to the plane of the white organic light emitting display device by the microlenses of the external light reflection blocking layer. As a result, the incident external light is trapped in any layer of the white organic light emitting display device or is destroyed by extinction interference. As the reflection of the incident external light is minimized, the visibility of the image to be displayed by the white organic light emitting display device is further improved.

 FIG. 8 is a schematic cross-sectional view of a top-emission type white organic light emitting display according to another embodiment of the present invention.

In the organic light emitting diode display, a top emission scheme is a scheme in which light emitted from an organic light emitting diode is emitted to the opposite side of a substrate on which a driving element including a thin film transistor for driving the organic light emitting display is located it means.

Referring to FIG. 8, a white organic light emitting diode display 800 including no polarizer according to another exemplary embodiment of the present invention includes a first substrate 810, a first electrode layer 831, A light emitting layer 832, a second electrode layer 833, a sealing layer 840 and a color forming layer 820, and a second substrate 850. 8 is a cross-sectional view of four pixels including a red pixel, a green pixel, a blue pixel, and a white pixel, which are the minimum unit pixel bundles of the white OLED display 800 for convenience of explanation. In this case, for convenience of description, the respective pixels are shown as being arranged in the same width, but the structures of the pixels viewed from the plane other than the actual cross-section are not arranged in the same width, and may have various structures.

The first substrate 810 is formed of a transparent insulating material. For example, the first substrate 810 may be a glass substrate or a plastic substrate such as a polyimide having flexibility. A driving and switching thin film transistor including a gate electrode, an active layer, a source electrode, and a drain electrode on this first substrate 810 and a metal wiring including a compensation circuit, a gate line, a data line, A driving element is formed. The organic light emitting element is driven and controlled by a driving element located on the first substrate 810. The red pixel region R, the green pixel region G, the blue pixel region B, and the white pixel region (hereafter referred to as " W) can be defined.

The organic light emitting diode 830 includes a first electrode layer 831, an organic light emitting layer 832, and a second electrode layer 833.

The first electrode layer 831 is an electrode layer positioned on the opposite side to the direction in which light emitted from the organic light emitting layer 832 is emitted, and thus is light reflective. In addition, since it has to function as an electrode, it has excellent electric conductivity. In addition, since the organic light emitting diode must be formed for every pixel region, the first electrode layer 831 connected to the driving thin film transistor is a pixel electrode separated for every pixel region. For example, the first electrode layer 831 may be connected to the source electrode or the drain electrode of the driving thin film transistor included in the driving device and may include an anode. At this time, when the first electrode layer 831 is an anode, the work function value of the first electrode layer 831 is high. That is, in the case of the top emission type, the first electrode layer 831 may include a material having electrical conductivity and light reflectivity, a high work function value and functioning as an anode, and may be separated to correspond to each pixel region. The first electrode layer 831 may be formed of a transparent conductive oxide (TCO) having a high work function value such as ITO (indium tin oxide), IZO (indium zinc oxide), ZnO A layer made of a material having a high work function value such as silver (Ag), and the like, but it is not limited thereto.

The organic light emitting layer 832 forms white light. The organic light emitting layer 832 may include several light emitting portions (not shown) that emit light of different colors, which are stacked with a charge generation layer (not shown) therebetween. The color of the light emitted from the first light emitting portion (not shown) is complementary to the color of the light emitted from the second light emitting portion (not shown), and the light emitted from the first light emitting portion (not shown) (Not shown) are combined to finally form white light. For example, a charge generating layer (not shown) is disposed on a first light emitting portion (not shown) for generating yellow-green light and a second light emitting portion (not shown) for generating blue light on a charge generating layer ) Can be located.

The second electrode layer 833 is an electrode layer positioned on the opposite side of the direction in which light emitted from the organic light emitting layer 832 is emitted, and thus is light reflective. In addition, since it has to function as an electrode, it has excellent electric conductivity. For example, when the first electrode layer 831 includes an anode, the second electrode layer 833 may include a cathode. In this case, when the second electrode layer 833 is a cathode, the work function value of the second electrode layer 833 is lower than that of the first electrode layer 831. That is, in the case of the top emission type, the second electrode layer 833 includes a material having a conductivity and a light transmittance and a low work function value to function as a cathode. For example, the metal layer may include a single layer of a metal layer having a low work function value and a high light transmittance, or may include a metal layer having a low work function value and a metal layer having a high light transmittance, And may include an alloy of excellent metals or an alloy layer. The second electrode layer 833 may be formed by forming a very thin metal layer made of an alloy of magnesium (Mg) and silver (Ag) having a relatively low work function, for example, to ensure light transmittance and a transparent conductive metal But are not limited to, a metal layer of a series of materials.

The sealing layer 840 prevents ultraviolet rays, oxygen, and moisture from penetrating into the white organic light emitting display device 800, thereby preventing the organic light emitting device from being deteriorated. The sealing layer 840 may be formed by forming an ultraviolet curing sealant on the outermost side of the white organic light emitting diode display 800 in a state where the second electrode layer 833 is formed and then placing the moisture absorbent Getter in the center, Method. Alternatively, the sealing layer 840 may be formed by forming a material including an inorganic powder such as glass at the outermost edge of the white organic light emitting diode display 800 in a state where the second electrode layer 833 is formed, Or by a flit sealing method. Alternatively, the sealing layer 840 may be formed by a face sealing method in which an ultraviolet ray or a thermosetting sealant is formed on the entire surface of the white organic light emitting diode display 800 in a state where the second electrode layer 833 is formed . Alternatively, the sealing layer 840 may be formed by a thin film encapsulation (TFE) method including an organic insulating layer and a protective layer including an alternately stacked inorganic material. At this time, the inorganic material includes at least one selected from aluminum oxide, zinc oxide, zirconium oxide, hafnium oxide, lanthanum oxide, titanium oxide, silicon nitride, and silicon oxide. At this time, the organic insulating layer functions to cover the foreign object and flatten the surface.

The color-forming layer 820 is a layer in which the white light formed by the white organic light emitting diode display 800 emits red light, green light, and blue light in each of the red pixel region R, the green pixel region G, and the blue pixel region B, A color filter layer and an external light reflection preventing layer. The color forming layer 820 may have various structures as described above with reference to FIGS.

2 to 7 of the lower emission type white organic light emitting display device are applied as they are but the emission direction of light generated in the upper emission type is not limited to the organic emission layer 832 The color forming layer 820 should be positioned on the second electrode layer 833 and the positions of the constituent elements of each of the color forming layers 820 should be lower than that of the first electrode layer 831. [ All of the positions are reversed when compared with the position in the light emitting mode.

The second substrate 850 is formed of a transparent insulating material. For example, the second substrate 850 may be a glass substrate or a plastic substrate such as a polyimide having flexibility.

Hereinafter, the reduction of the external light reflectance of the white organic light emitting display according to the use of the external light reflection preventing layer will be described in more detail.

9A and 9B, the element a, the element b of the first embodiment, and the element c of the first embodiment are cases in which an external light reflection prevention layer including scattering particles is applied to the green organic light emitting element of the lower emission type, Is a case where the external light reflection prevention layer is not applied to the green organic light emitting element of the lower emission type.

Example 1 A 3 mm * 3 mm square organic light emitting device emitting green light was fabricated on an external light reflection blocking layer formed on a glass substrate with a square of 3 mm * 3 mm. More specifically, in the case of the external light reflection preventing layer, 10 wt% of alkali soluble resin (methacrylic acid (MMA): glycidyl methacrylate (GMA): styrene 2: 5: 2 copolymer) (OXE-01_Ciba) was contained in an amount of 15 wt%, the light-extraction dispersion (MHI White C024_Mikuni) was 20 wt%, the photo-polymerization initiator (OXE-01_Ciba) The composition containing 52% by weight of a solvent ([PGMEA / Cyclohexanone] _ purge solution) was stirred at room temperature and then spin-coated (700 rpm, 30 seconds) Exposed to light using a mask, immersed in a developing solution (0.04%, KOH) for 100 seconds for development, and baked in an oven at 230 캜 to form an external light reflection blocking layer. And a second overcoat layer (D1_Brewer Science) having a refractive index of about 1.7 was formed thereon by spin coating at 0.5 탆. At this time, the scattering particles contained in the external light reflection preventing layer are spherical titanium oxide (TiO2) of about 0.6 mu m in diameter contained in the light extracting dispersion. A green organic light emitting device was formed on the external light reflection blocking layer and the second overcoat layer. More specifically, a green organic light emitting device is formed by forming 500 Å of an anode (ITO) corresponding to one first electrode layer, 50 Å of a hole injection layer (LGC101) thereon, on the external light reflection preventing layer and the second overcoat layer A green light emitting host H111 doped with a green light emitting dopant GD270 at a weight ratio of 4% was formed to a thickness of 300 Å, a hole transport layer EL301 was formed thereon with a thickness of 700 Å, and an electron transport layer (TRE314) And a cathode (LiF: Al) corresponding to the electron injection layer to the second electrode layer was formed thereon in a thickness of 800 Å.

Example 1 In the device b, a 3 mm * 3 mm square organic light emitting device emitting green light was fabricated on an external light reflection blocking layer formed on a glass substrate with a square of 2.8 mm * 2.8 mm. More specifically, the organic light-emitting device was fabricated so that the green organic light-emitting device was positioned from the four corners of the external light reflection-blocking layer to the point where it extended 0.2 mm each while covering the external light reflection- Do. That is, the area of the external light reflection preventing layer is smaller than the area of the green organic light emitting element, and the whole area of the external light reflecting and blocking layer overlaps with the green organic light emitting element.

Example 1 On a glass substrate, a 3 mm * 3 mm square organic light emitting device emitting green light was fabricated on an external light reflection blocking layer formed with a square of 2.9 mm * 2.9 mm. More specifically, it is the same as the device 1 of Example 1, except that the green organic light emitting device is positioned from the four sides of the external light reflection preventing layer to the points extending by 0.1 mm each while covering the external light reflection preventing layer . That is, the area of the external light reflection preventing layer is smaller than the area of the green organic light emitting element, and the whole area of the external light reflecting and blocking layer overlaps with the green organic light emitting element.

And that the external light reflection preventing layer is not applied to the comparative element 1, which is the same as the element a of the first embodiment.

Referring to FIG. 9A, the average external light reflectance in the entire 3 mm * 3 mm square was measured for the device a, the device b of Example 1, the device c of Example 1, and the wavelength band of the comparative device 1 manufactured as described above Let's look at the results. At this time, the external light reflectance was measured using a DMS (Display Measurement System) -803 model of Autronic-MELCHERS, which is an apparatus capable of evaluating electro-optical characteristics of a flat panel display device and analyzing according to transmission or reflection options . All reflectance measurements were made using this equipment.

In FIG. 9A, the X-axis represents all wavelength bands of the light emitted from the measurement equipment (that is, external light in the case of the measurement object), and the Y-axis represents the light emitted from the measurement equipment The average value of the reflectance of the object (referred to as the total external light reflectance of the whole area by wavelength) is shown by wavelength band.

The reflectance of the element a in Example 1, the element b in Example 1, and the element c in Example 1 are low, as compared with the comparative element 1 to which the external light reflection prevention layer is not applied. More specifically, the reflectance of the element a, the element b and the element c of Example 1 in any wavelength band region exceeded 40%, as compared with the comparative element 1 in which the wavelength band region having a reflectance exceeding 50% exists, .

With reference to FIG. 9B, for each of the device a, the device b, the device c, and the comparative device 1 manufactured in the above-described Example 1, the total area of 3 mm * 3 mm square, Let us examine the result of measuring the average external light reflectance.

9B, the X-axis represents a viewing angle of up to 60 degrees with respect to the central vertical direction of the object to be measured, and the Y-axis represents the ratio of the total reflection area of the object to be measured And the average value (referred to as the average external light reflectance of the whole region of the entire region by the viewing angle). The reflectance of the comparative element 1 without application of the external light reflection prevention layer increases abruptly at a viewing angle of about 35 DEG, whereas the reflectance of the element 1 of Example 1, the element b of Example 1, and the element c of Example 1 rapidly increase No sections are found. In contrast to the comparative element 1 in which the external light reflection preventing layer is not applied, the reflectance of the element a in Example 1, the element b in Example 1, and the element c in Example 1 is low. More specifically, in the first viewing angle, the reflectance between 30% and 40% at the front viewing angle in Example 1 element a, Example 1 element b, and Example 1 element c, as compared with Comparative Example 1 in which the reflectance exceeds 45% Lt; / RTI >

From this, it can be seen that the external light reflectance is remarkably low in the first embodiment elements as compared with the comparative element 1 in which the external light reflection preventing layer is not applied at the front viewing angle. Further, in view of the change of the external light reflectance according to the viewing angle, It can be seen that the device of Example 1 is stable without increasing relatively rapidly while the viewing angle is increased sharply.

The device a of Example 1, the device b of Example 1, the device c of Example 1, and the comparative device 1 of Figs. 10A and 10B, respectively, were manufactured as follows.

10A and 10B, the device a, the device b of the second embodiment, and the device c correspond to the case where an external light reflection prevention layer including scattering particles is applied to the green organic light emitting device of the lower emission type, and the comparison device 2 And the external light reflection preventing layer is not applied to the green organic light emitting element of the lower emission type.

Example 2 Element a, Example 2 Element b, Example 2 Element c and Comparative Element 2 all applied the same organic light emitting element as the lower organic emission element of Example 1 element a.

Example 2 In Example 2, a negative photoresist material was applied by spin coating (700 rpm, 30 seconds) to a thickness of 1 mu m on the substrate and exposed using a mask at 100 mJ / cm < ² > The resultant was immersed in developing solution (0.04%, KOH) for 100 seconds to develop, and baking was performed in an oven at 230 캜 to form an external light reflection preventing layer having a microlens shape. The microlens shape was also fabricated by photolithography using a mask. And a second overcoat layer (D1 Brewer Science Co.) was spin-coated thereon to a thickness of 0.5 mu m. And a green organic light emitting device was formed thereon. That is, the external light reflection preventing layer is the same as the element a of Embodiment 1, except that it has a microlens shape having a diameter of 2 占 퐉.

Example 2 The same as the device 2 of Example 2 except that the external light reflection preventing layer in the device b had a diameter of 4 micrometers in the microlens shape.

Example 2 The same as element 2 of Example 2, except that the diameter of the microlens shape included in the external light reflection-blocking layer in the element c was 3 占 퐉.

And in Comparative Example 2, the external light reflection preventing layer is not applied.

Referring to FIG. 10A, the average external light reflectance in the entire 3 mm * 3 mm square area was measured for each of the device a, the device b, the device c and the comparative device 2 manufactured as described above Let's look at the measurement results.

The X axis and Y axis in Fig. 10A are the same as those in Fig. 9A.

The reflectance of the device 2 of Example 2 and the device 2 of Example 2 are lower than that of the comparative device 2 to which the external light reflection preventing layer is not applied. More specifically, it can be seen that the reflectance does not exceed 40% in any wavelength band region in the device 2 of Example 2 and the device 2 of Example 2, as compared with the comparative device 2 in which the wavelength band region having a reflectance exceeding 50% exists . Example 2 In the case of the element a, the reflectance is higher than that of the comparative element 2. From this, it can be expected that the effect of lowering the reflection of the external light can be expected if the shape of the microlens formed in the external light reflection- .

Referring to Fig. 10B, in all of the 3 mm * 3 mm squares of the device 2 of Example 2, the device 2 of Example 2, the device 2 of Example 2, and the comparative device 2 manufactured as described above, The average external light reflectance is measured.

The X axis and Y axis in Fig. 10B are the same as those in Fig. 9B.

The reflectance of the comparative element 2 to which the external light reflection preventing layer is not applied increases abruptly at a viewing angle of about 35 DEG, whereas the reflectance of the element 2 of Example 2, the element b of Example 2, and the element c of Example 2 abruptly increase No sections are found. Rather, in the case of Example 2, the reflectance decreases as the viewing angle increases. The device 2 of Example 2 and the device c of Example 2 have lower reflectance than the comparative device 2 to which the external light reflection preventing layer is not applied. More specifically, in the full-viewing angle, the reflectance is maintained between 30% and 40% at the front viewing angle in the device 2 of Example 2 and the device 2 of Example 2, as compared with the comparative device 2 where the reflectance exceeds 45%.

From this, it can be seen that the external light reflectance of the device of Example 2 is remarkably low as compared with the comparison device 2 to which the external light reflection preventing layer is not applied at the front viewing angle. Further, from the viewpoint of the change of the external light reflectance according to the viewing angle, It can be seen that the device of Example 2 is stable without increasing relatively rapidly while the viewing angle is increased sharply.

A white organic light emitting display device that does not include a polarizing plate includes a first substrate on which a red pixel region, a green pixel region, a blue pixel region, and a white pixel region are defined and includes a color forming layer located on a first substrate, A second electrode layer, and an encapsulating layer, wherein the color-forming layer includes an external light reflection-blocking layer and a color filter layer, and the color filter layer is formed so as to correspond to a red pixel region, a green pixel region, and a blue pixel region, respectively A first color filter, a second color filter and a third color filter which are separated from each other and located on the same plane, and the external light reflection prevention layer is located in the white pixel region.

At this time, the color-forming layer is positioned between the first overcoat layer and the external light reflection-blocking layer, which is located between the external light reflection-blocking layer and the color filter layer and alleviates or removes the step of the color filter layer, And a second overcoat layer.

At this time, the external light reflection blocking layer may be located in the red pixel region, the green pixel region, and the blue pixel region. At this time, the external light reflection blocking layer overlaps the entire area of the color filter layer and may be a single continuous layer in the red pixel region, the green pixel region, the blue pixel region, and the white pixel region. At this time, the external light reflection blocking layer is divided into a first external light reflection blocking layer, a second external light reflection blocking layer, a third external light reflection blocking layer and a second external light blocking layer separated to correspond to the red pixel region, the green pixel region, the blue pixel region and the white pixel region, Wherein the first external light reflection prevention layer overlaps the first color filter and the second external light reflection prevention layer overlaps the second color filter and the third external light reflection prevention layer overlaps with the third color Filter, and the fourth external light reflection blocking layer may be located in the white pixel region. At this time, the fourth external light reflection blocking layer may be located on the same plane as the color filter layer, and the second overcoat layer may be located on the fourth external light reflection blocking layer and the color filter layer. At this time, the first external light reflection blocking layer may be in direct contact with the first color filter, the second external light reflection blocking layer may be in direct contact with the second color filter, and the third external light reflection blocking layer may be in direct contact with the third color filter. At this time, if the area of the first external light reflection blocking layer is smaller than the area of the first color filter, the area of the second external light reflection blocking layer is smaller than the area of the second color filter, May be smaller than the area of the third color filter. At this time, only a part of one surface of the first external light reflection preventing layer overlaps one surface of the first color filter, or only part of one surface of the second external light reflecting preventing layer overlaps one surface of the second color filter, 3, only a part of one surface of the external light reflection preventing layer can overlap with one surface of the third color filter.

At this time, the external light reflection blocking layer may include scattering particles containing at least one selected from titanium oxide (TiO ₂ ), zirconium oxide (ZrO ₂ ), and barium titanate (BaTiO ₃ ). At this time, the second overcoat layer is in direct contact with the external light reflection blocking layer, and the step of the external light reflection blocking layer is relieved or removed, and the refractive index can be 1.65 or more.

At this time, the external light reflection blocking layer may be formed in a microlens shape, and the microlens shape may be concave or convex. At this time, the external light reflection blocking layer may be a single layer that overlaps the entire area of the color filter layer and is continuous in all pixel areas. At this time, the microlens shape may be located only in the region corresponding to the white pixel region. At this time, in the microlens shape, the diameter of the lens is 2 μm or more and 6 μm or less, and the first electrode layer and the external light reflection prevention layer can directly contact each other.

In the case of the white organic light emitting display device of the lower emission type, in the color formation layer, the external light reflection prevention layer is positioned in the same plane as the color filter layer or below the color filter layer, the first electrode layer is located on the color formation layer, The light emitting layer is located on the first electrode layer, the second electrode layer is located on the organic light emitting layer, is light reflective, and the sealing layer can be located on the second electrode layer.

In the case of the top emission type white organic light emitting display, the first electrode layer is light reflective, the organic light emitting layer is positioned on the first electrode layer, the second electrode layer is positioned on the organic light emitting layer and is light transmissive, And in the color-forming layer, the external light reflection-blocking layer may be located on the same plane as the color filter layer or on the color filter layer, and the sealing layer may be located on the color-forming layer.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The scope of protection of the present invention should be construed according to the following claims, and all technical ideas within the scope of equivalents should be construed as falling within the scope of the present invention.

110, 810: a first substrate
120, 220, 320, 420, 520, 620, 720, 820:
130, 830: organic light emitting element
131, 831: first electrode layer
132, 832: organic light emitting layer
133, 833: the second electrode layer
140, 840: sealing layer
250, 350, 450, 550, 650, 750: Color filter layer
251, 351, 451, 551, 651, 751: a first color filter
252, 352, 452, 552, 652, 752:
253, 353, 453, 553, 653, 753: third color filter
261, 361: a first overcoat layer
262, 362, 462, 562, 662, 762: the second overcoat layer
270, 370, 470, 580, 680, 780:
371, 471, 781: a first external light reflection preventing layer
372, 472, 782: a second external light reflection prevention layer
373, 473, 783: a third external light reflection blocking layer
374, 474, 784: Fourth external light reflection blocking layer
850: second substrate
100, 800: white organic light emitting display

Claims (18)

In a white organic light emitting display device not including a polarizing plate,
A first substrate on which a red pixel region, a green pixel region, a blue pixel region, and a white pixel region are defined; And
A first electrode layer, an organic light emitting layer that emits white light, a second electrode layer, and an encapsulating layer, the color forming layer being disposed on the first substrate,
Wherein the color forming layer includes an external light reflection blocking layer and a color filter layer,
Wherein the color filter layer includes a first color filter, a second color filter, and a third color filter which are separated so as to correspond to the red pixel region, the green pixel region, and the blue pixel region, respectively,
Wherein the external light reflection blocking layer is located in the white pixel region.
White organic light emitting display. The method according to claim 1,
The color-
A first overcoat layer positioned between the external light reflection blocking layer and the color filter layer to alleviate or remove a step of the color filter layer and a second overcoat layer disposed directly adjacent to the external light reflection blocking layer, Overcoat layer. ≪ RTI ID = 0.0 > 11. < / RTI &
White organic light emitting display. The method according to claim 1,
Wherein the external light reflection blocking layer is also located in the red pixel region, the green pixel region, and the blue pixel region.
White organic light emitting display. The method of claim 3,
Wherein the external light reflection blocking layer overlaps the entire area of the color filter layer and is a continuous single layer in the red pixel region, the green pixel region, the blue pixel region, and the white pixel region.
White organic light emitting display. The method of claim 3,
Wherein the external light reflection blocking layer is divided into a first external light reflection blocking layer, a second external light reflection blocking layer, and a third external light reflective blocking layer which are separated to correspond to the red pixel region, the green pixel region, the blue pixel region, Layer and a fourth external light reflection blocking layer,
Wherein the first external light reflection blocking layer overlaps with the first color filter,
The second external light reflection blocking layer overlaps with the second color filter,
The third external light reflection blocking layer overlaps with the third color filter,
And the fourth external light reflection blocking layer is located in the white pixel region.
White organic light emitting display. 6. The method of claim 5,
And the fourth external light reflection blocking layer is located on the same plane as the color filter layer.
White organic light emitting display. The method of claim 6, wherein
Further comprising a second overcoat layer disposed on the color filter layer and the fourth external light reflection blocking layer.
White organic light emitting display. 6. The method of claim 5,
Wherein the first external light reflection blocking layer is in direct contact with the first color filter,
Wherein the second external light reflection blocking layer is in direct contact with the second color filter,
And the third external light reflection blocking layer is in direct contact with the third color filter.
White organic light emitting display. 6. The method of claim 5,
Wherein an area of the first external light reflection blocking layer is smaller than an area of the first color filter,
The area of the second external light reflection blocking layer is smaller than the area of the second color filter,
And the area of the third external light reflection blocking layer is smaller than the area of the third color filter.
White organic light emitting display. 6. The method of claim 5,
Only a part of one surface of the first external light reflection blocking layer overlaps with one surface of the first color filter,
Only a part of one surface of the second external light reflection blocking layer overlaps one surface of the second color filter,
Wherein only a part of one surface of the third external light reflection blocking layer overlaps one surface of the third color filter.
White organic light emitting display. The method according to claim 1,
Wherein the external light reflection blocking layer includes scattering particles,
Characterized in that the scattering particles comprise at least one selected from the group consisting of titanium oxide (TiO ₂ ), zirconium oxide (ZrO ₂ ) and barium titanate (BaTiO ₃ )
White organic light emitting display. 12. The method of claim 11,
Further comprising a second overcoat layer positioned immediately adjacent to the external light reflection blocking layer to mitigate or eliminate the step of the external light reflection blocking layer and having a refractive index value between the refractive index of the external light reflection blocking layer and the refractive index of the first electrode layer ≪ / RTI >
White organic light emitting display. The method of claim 1, wherein
Wherein the external light reflection blocking layer is formed in a microlens shape,
Characterized in that the microlens shape is a concave shape or a convex shape.
White organic light emitting display. The method of claim 13, wherein
Wherein the external light reflection blocking layer overlaps the entire area of the color filter layer and is a continuous single layer in the red pixel region, the green pixel region, the blue pixel region, and the white pixel region.
White organic light emitting display. The method of claim 14, wherein
Wherein the microlens shape is located only in a region corresponding to the white pixel region.
White organic light emitting display. The method of claim 13, wherein
In the microlens shape, the diameter of the lens is 8 占 퐉 or less,
Wherein the first electrode layer and the external light reflection blocking layer are in direct contact with each other.
White organic light emitting display. The method according to claim 1,
In the color-forming layer, the external light reflection blocking layer may be located in the same plane as the color filter layer or below the color filter layer,
Wherein the first electrode layer is disposed on the color forming layer and is light-
Wherein the organic light emitting layer is disposed on the first electrode layer,
Wherein the second electrode layer is positioned on the organic light emitting layer and is light reflective,
Characterized in that the sealing layer is located on the second electrode layer.
White organic light emitting display. The method according to claim 1,
Wherein the first electrode layer is light reflective,
Wherein the organic light emitting layer is disposed on the first electrode layer,
Wherein the second electrode layer is disposed on the organic light emitting layer and is light-
Wherein the color forming layer is disposed on the second electrode layer,
In the color-forming layer, the external light reflection-blocking layer may be located on the same plane as the color filter layer or on the color filter layer,
Characterized in that the sealing layer is located on the color forming layer.
White organic light emitting display.

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